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Overview

During the authorize request of an implicit or authorization code flow (Open ID or OAuth), a 400 Bad Request error appears.

Applies ToAuthorize (GET /authorize https://developer.okta.com/docs/api/resources/oidc#authorize) request of 

• Implicit Flow
• Authorization Code Flow

CauseThis error is returned because the value of ${redirect_uri} used in authorize request is not registered in the Open ID client in Okta, as an allowed Login Redirect URI

ResolutionIn the following example authorize request

https://example.okta.com/oauth2/v1/authorize?client_id=0oais56vveNLSDqby0x7&scope=openid+profile&response_type=id_token&response_mode=fragment&nonce=1234&redirect_uri=

http://localhost:8888/my-app/signin.html/&state=someState

Make sure that redirect _uri = http://localhost:8888/my-app/signin.html/​ is registered as an allowed Login redirect URI in Open ID Client (using client id 0oais56vveNLSDqby0x7 in the example above)

1. From the Applications page of the Okta Admin Console, click on your OpenID application (you can also navigate here directly by using the URL that appears in the error description)
2. In the General tab, click Edit and add http://localhost:8888/my-app/signin.html/​ as a Login redirect URI. Please note that the Login redirect URIs you provide here must be an exact, case sensitive match (including trailing slashes) with the URI you are including in your authorize request. If the redirect_uri does not exactly match one of the Login redirect URIs, you will continue to encounter this error
3. Click Save and General settings should look like:

If any of the information is not visible, the full article can be found here:

https://support.okta.com/help/s/article/The-redirect-uri-parameter-must-be-an-absolute-URI?language=en_US